Hiram stevens maxim



" NITED STAT-Es.

PATENT OFFICE.

MAN UF ACT U RE 'OF exPLos'lvEs.

SPECIFICATION forming part of Letters Patent No. 436,898, dated September 23,1890

Original application filed December 19, 1888, Serial No. 294,087- 324,336- (No specimens.) Patented in England November 8, in Spain February 20, 1888,1Io. 8,991.

Divided and this application i'iled September 18, 1889. Serial lie. 1888,1Io. 16,213; in France December 1888, No. 194,792, and

To all whom it may concern:

Be it known that I, HIRAM STEVENS MAXIM, mechanical engineer, a citizen of the United States, and a resident of London, England,

have invented certain new and useful Im-.

Spain, No. 8,991, dated February 20, 1889,)of

which the following is a specification.

This application is a division of an application filed by me December 19, 1888, Serial No. 294,087: 1

My invention relates to the manufacture ofexplosives foruse in fire-arms and for other purposes.

The main object of my said invention is to provide an explosive which will be comparatively smokeless, or will by its combustion produce much less smoke than ordinary gunpowder, and which when used in a fire-arm will burn slowly as compared with ordinary gun-cotton and-will .exerta high and cont-inuous pressure on the projectile?- Gun-cotton has most of the elements or qualities requisite in an explosive for use in firearms-that is to say, when properly prepared it is stable and very powerful, it produces but a small quantity of smoke, does not injure metallic cartridge-cases, and is not suffieiently hygroscopic to impair its efficiency.

.As hitherto manufactured, however, it has the disadvantage that it is too quick or sudden in its action. I obviate this defect by my invention, hereinafter described,

Attempts have .heretofore'becn made to.

manufacture explosives from collodion obtained by the treatment of the low grades of gun-cotton with ether and alcohol. By the low grades of gun-cotton I mean thosewhich are readily soluble in ether or alcohol or in a mixture of these substances, and which contain buta smallpercentage of oxygen. These low grades of gun-cottonare unstable, do not withstand the action of sunlight, and as they do not contain sufficient oxygen to consume all of the vegetable matter of which they are.

composed they produce in burning a large quantity of smoke.

When gun-cotton 1S dissolved, it forms a thick gelatinous mass, which is very difficult to manipulat'c'by the means heretofore used for this purpose; Moreover, in the methods 5 5 of manufacture heretofore adopted a very A large quantity of liquid or solvent is required to bring the gun-cotton to such a consistency that it can be spread out tobe dried. Consequently the manufacture of explosives from gun-cotton has hitherto been very costly.

In my application filed December 19, 1888, Serial No. 294,087,1- have described a process of manufacturing explosives from gun -cotton which involves the novel feature of treating the gun-cotton with a solventsuch as acetone, ethylic acetate, or the like-iii the condition of vapor. The method also involves the plan of placing the gun-cotton in an airtight cylinder or receiver, exhausting the air, then admitting the solvent, and then forcing the material out through a contracted aperture and dividing it up into small pieces.

My present invention isin the nature of a modification of this process, the main object being to diminish the rapidity of explosion, as previously stated. This I have found may be done .by partially gelatinizing or dissolving the gun-cotton and then compressing it, and thus forming it into very hard sheets or cakes, which may be cut or divided-into pieces or. grainsof any desired size.

In carrying out my inventionI take a suitable quantity of high-grade or highly-oxplosive gun-cotton and reduce itto pulp in a paper-pulping machine, rag-engine, or other "'convenicnt machine. I then wash it thoroughly with water or other suitable liquid to. remove any free acid that it may contain,

moistened with acetone and subjected to the action of a mixture of sixparts of ether to one of alcohol until itis partially dissolved.

' When it has lI/lllTS been suflieiently sof-teiied,

it is compressed into-a solid cake or sheet 5 and allowed to dry.

The press used for (thus forming the partially-dissolved gun-cotton into sheets or and then dry it. The dried pulp is then o cakes should be a very strong one, and-the pressure applied to the material should be very high-higher than it would be likely to encounter in the gun. I prefer to subject the material to a pressure of from twenty to forty tons per square inch. In some cases it may be advantageous to apply a moderate amount of heat to the material while in the press. The cake orsheet of solidified or compressed gun-cotton thus obtained is cut'up into small cubes or pellets. These cubes may have their corners rounded by rumbling or othersuitable'means.

Instead of compressing the gun-cotton in the above-described manner, it maybe forced while in a plastic condition through dies, and the strips or threads cut up after issuing from the dies.

If the explosive as thus made is found to burn too quickly for a given purpose, any suitable substance or substances are' mixed with the gun-cotton, which will have a tend- "ency .to diminish the rate of combustion thereof. i

A mixture of fmineralwax or resinous matter or of a hydrocarbon with some oxygenbearlng salt like nitrate of potash or of soda or chlorate of potash is sometimes added to 'or combined with .the gun-cotton to facilitate solidification and diminish the rate of burning. In some instances I combine with the gelatinized mass of partially-dissolved guncotton a small percentage of nitrate of potash or of soda or chlorate of potash or other oxygen-bearing salts, and in other instances a larger percentageof chlorate of potash and about one per cent". of parafiine-wax.

A modification of the above-described process consists in first forming the gun-cotton I place the gun-cotton or the pulp in a suit-.

ably-shaped receiver and exhaust the air therefrom, and then allow the vapor of the solvent to enter the said receiver and act on the mass until the same becomes to a certain degree sticky or partly dissolved. Then without admitting any air'I compress the mass and solidify it and withdraw it as a whole from the said receiver. Large and solid pieces may thus be formedwhich are quite free from airbubbles.

thus formed may be cut or dividedinto small pieces or grains in any convenient manner.

Blocks of the explosive material Gun-cotton as hitherto manufactured when used in a gun explodes too suddenly, because 65 the higl' pressure set up in the chamberof the gun fo e the inflamed gases into the interstices'oi in; mass and thus instantly ignites the whole of the said mass. \Vhen,however, it is made, as above described, in lumps or grains of considerable size and in such a state process the low and soluble grades of guncotton are dissolved with ether, thus forming collodion. The collodion is then intimately combined with gun-cotton, which is highly explosive, and is insoluble, or nearly so, in ether, the'collodion being sufficient to cause the gun-cotton to adhere in a solid mass. As

the low grades have less oxygen than the high" grades, I find it advantageous in this case to employ chlorate of potash or other-oxygenbearing salt to supply the additional oxygen required.

The gun-cotton may,if desired, be first made into paper and then partly gelatinized and compressed. I find it more advantageous,

however, to first reduce the gun-cotton to pulp and then treat it as above described, this being the most effectual method of removing the free acid usually present.

The product formed by the method of man ufacture above described is very hard, resembling horn. It does not injure metallic cartridge-cases, is not sufiiciently hygroscopic to impair its elfectiveness, is very powerful, and it burns much slower than ordinary gun-cotton,.while it gives very little smoke and produces a high and continuous pressure. It is therefore well adapted for use in cases where the above qualities, and notably the absence of smoke, are desirable.

Vhat I claim is- 1. The method or process herein described of manufacturing explosives from gun-cotton, which consists in confining the gun-cotton in a receiver, exhausting the air from the same, then introducing a vaporized solvent into the exhausted receiver until the gun-cotton is partiallydissolved.then compressingit,and then I dividing it up into small pieces or grains, 'as set forth.

2. The method of manufacturing explosive material, which consists in reducing gun-cotton-to pulp and drying the same, subjecting the pulp in a suitable receiver to the action of vaporized aceto'ne or itsspecified equivalent, then compressing it by a pressure greater than that to which it is liable to be exposed in a gun, and dividing it up into small pieces or grains.

In test-imony whcreof I have hereunto signed my name in the presence of two subscribing witnesses.

llIRAM STEVENS MAXIM. itnesses:

DAVID YOUNG, CHAS. B. BURDON. 

